Electric switch



Nov. 6, 1934. H. F. MCLOUGHLIN ET AL 1,979,277

ELECTRIC SWITCH Filed Aug. 1, 1929 2 Sheets-Sheet 1 IN VENT0R BY i744) ATTORNEYX WITNESSES.

Nov. 6, 1934.

H. M LOUGHLIN ET AL ELECTRIC SWITCH 1929 2 Sheets-Sheet 2 Filed Aug. 1

nvvnvrom: f gffgwb' d )7 BY 9% A TTORNEY Patented Nov. 6, 1934 L UNITED STATES PATENT OFFICE ELECTRIC SWITCH Harold Fletcher McLoughlin and Frank William Osborn, Birmingham, England Application August 1, 1929, Serial No. 382,712 In Great Britain June 12, 1929 3 Claims. (01. 200-70) This invention has reference to quick-make Figure l is a plan showing the lay-out of the and quick-break electric switches, wherein there switch, with the contact-blade assembly in its is interposed between the moving contact-blade off position. member and an operating handle, a snap-ac- Figure 2 isa section taken on the line 2-2, 5 tion spring mechanism so arranged that when Figure 1,showing the detention and release mechthe operating member is actuated, it first tensions anism which is interposed between the spindle or stresses the spring and then, when the spring of the operating? handle and the sleeve that is sufiiciently tensioned allows the said contactcarries the moving contact blades, and said mechblade member to be tripped or displaced by spring anisin is rotatably supported on the said spindle.

.110 action relatively to the operating member. This view shows the parts in the normal or new To enable this tensioning. of the snap-spring tral positions they assume at the commencement by the operating handle, means are embodied in of an ope a of the Switch in the Opening the mechanism for detaining the moving contact reetien. member during the initial or spring-tensioning Figure 3 is a view similar to Figure 2 but shows 15 displacement of thesaid handle and for releasthe parts in the positions they assume on coming the said contact handle when the spring is pletion of the opening of the switch and prior tensioned sufficiently to "impart the 'make or to the return of the controlling element and the break movement to the contact blade member, operating handle to their normal or neutral and the principal object of the present invention position. i 20 is to provide for such detention and release of the Figure 4 is a Section 011 the line Figure contact-member by a simple and compact, but showing the connection between the snap-action durable and efficient, mechanism such as can spring and the driving stirrups that are fixed rereadily be applied to or embodied in switches and Spectively to the operati lever Spindle and t0 switch-fuse combinations of various types. the carrier-sleeve of the moving contact blade 25 This object is realized according to the present assembly. invention by a mechanism in which there is in- Figure 5 is a transverse vertical section of the terposed between a controlling element connectcomplete switch. ed to and moving with the operating member, Figure 6 is a horizontal section on the line 6,6 and a controlled element connected to and movshowing the rotary contact member (in the oii 30 ing with the contact-member, a pawl or detenposition), and also the fixed contacts of the detion device which, on commencement of each vice. operation of the handle in either the make or Figure 7 is a horizontal section on the line '7--7 break direction, is positively displaced into deshowing the element of the detention mechanism. taining connection or engagement withthe con- The same letters of reference indicate corre- 35 trolled elementgand is held or retained in such sponding parts in the said Figures 1 to 4 of the engagement by the controlling element, but is drawings. released by the said controlling element and dis- In the ironclad switch shown, the spindle it engages the controlled element at the appropriof the operating handle a is journalled in bearate time for enabling the contact-member to be ings a2, a fixed in the opposite side-walls b b 40 actua d by e tensiened p of the enclosing box or casing. This spindle sup- The disenga e 0f the p wl 01' detention ports two sleeves 0, 0 that are free to turn device fromthe controlled element preferably is about the said spindle and respectively carry the effected (on the said pawl being released from insulated contact blades d (1 these sleeves bethe restraint imposed by the controlling element) ing coupled as a unit by a spring-abutment stir- 45 by movement transmitted to the pawl through rup e, whilst a similar but smaller abutmentthe controlled element from the snap action stirrup f is fixed to the spindle and is adapted to spring, and on being so disengaged, the pawl may move angularly within and relatively to the stirbe used as a stop for arresting or stopping the rup e. A coiled spring g having levering arms g1, parts of the switch that are displaced during the g is-so mounted on the spindle, between the sides 50 movement of the contact-blade assembly into of the spindle stirrup that its arms g 9 are its on or off position. opposed to opposite sides of the transverse por- An application of the invention to a double tions or bridge-bars e i of the twov stirrups. pole switch adapted for mounting in an enclos- Also the contact-member stirrup e carries on its ing box is shown in the accompanying drawings, opposite sides, pairs of inwardly-projecting ears in which 1 1 or. horns e c with one or other of which the stirill rup f is adapted to engage for positive driving or starting the make or break movement of the contact-blade assembly after the snap-action spring has been wound up or tensioned.

This arrangement of spring and abutment stirrups renders both arms of the spring available for use in tensioning the said spring, since whether the operating spindle and its stirrup f are turned in the opening or closing direction the bridge-bar f of the stirrup f levers against one of the spring arms, meanwhile the other springarm remains in abutment with the bridge-bar c of the stirrup e (which for the time being is locked by the contact-blade detention mechanism hereafter to be described) and thus enables the winding-up of the spring. Further, when the stirrup f has completed its spring-tensioning diu" placement, its bridge-bar may come into contact with a pair of horns e or e on the stirrup 'e for giving a positive starting drive to the contactblades at a moment which synchronizes with, or slightly follows, the release of the contact-blade assembly from the detention mechanism.

The detention mechanism is arranged inside the box adjacent to one of the bearings of the operating spindle, and comprises three elements, viz:-a pawl or detention star g a controlling element It and a controlled element 2'. The device W, in the particular construction illustrated, has the form of an equilateral triangle presenting three equidistant points or noses. g is journalled on a stud g fixed in the side wall b, of the box in appropriate relation to the centre of the operating spindle. The pawl-controlling element consists of a quadrant or sector plate which is keyed or otherwise secured to the spindle a and is located against the box wall h outwards of the pawl. This plate has a curved slot or clearance hole 71 which accepts the pawl-carrier stud g and it is also formed with an inwardly-projecting flange 71 having an angular measurement slightly greater than the angular distance through which the operating spindle has to be turned for effecting the tensioning of the snap-spring. The pawlcontrolled element or flyer i, which is a fixture to one of the sleeves of the contact-blade assembly, is constituted by another and smaller quadrant or sector plate, having in the periphery which is concentric with the flange 71, of the pawl-controlling quadrant h, two counterpart recesses i 1' which are disposed on opposite sides of the spindle center, in positions respectively corresponding to the ofi and on positions of the contact blades. Each recess presents, on its inner side, a shoulder with which the pawl engages when looking the flyer, whilst outwards of each recess is a stop heel i adapted to co-act with the pawl for stopping the spring-actuated parts on completion of the make or break movement. As will be seen from Figures 2 and 3, the flange 7L occupies only the middle sector of the periphery of the quadrant h and is substantially smaller in angular dimensions than is the clearance slot h In the construction illustrated, and after each spring-actuation of the contact member and during the subsequent return of the operating member and the controlling element It to their normal or neutral positions, the pawl g is positively moved by the said element It into detaining engagement with the flyer and is locked in that engagement (as shown in Figure 2) by the overhanging flange W. This lock is maintained, during the next spring-stressing movement of the operating member, by the said flange h riding over the said pawl, but when the flange clears the pawl oncompletion of the stressing of the snap-action spring, the said pawl is tripped, by the spring reaction transmitted to it through the flyer, so that it releases the said flyer to permit of the spring actuation of the contact-member assembly and then assumes a position (as shown in Figure 3) wherein a nose thereof lies in the path of one of the stop-wheels 2' of the flyer. This enables the pawl to serve as a stop for the spring-driven parts, and during the subsequent return of the operating member a and controlling element It to their neutral or normal position, the end of the flange I2 acts upon the pawl to positively re-set the same into detaining engagement with the flyer, whilst on completion of the said return movement, the said flange is engaged over the said pawl to lock the same in the said engagement ready for the next operation of the switch.

Mechanism as above described, Figures 5, 6 and 7 of the drawings, show an application of the invention to a rotary non-ironclad surface switch.

In the switch shown in these figures, the parts are designed and arranged to enable their mounting on a circular insulating base 0 of relatively small dimensions and their enclosure within a cover 0 and the moving contact-assembly is adapted to oscillate in a plane parallel to the base for taking the contact blades d thereof into and out of connection with the fixed contacts d The moving contact member is suitably insulated from its operating spindle, and an insulating partition p is located between the current carrying parts and a chamber 0 in the switchbase wherein the detention mechanism is located.

The base "end of the operating spindle a (to which the external handle or turn-button a is attached) is surrounded by a sleeve e that forms .part of the moving contact-member assembly and the spindle and sleeve respectively carry stirrups e and j which are associated with a double-armed spring g, g g and are arranged to provide for the tensioning of the spring and for the transmission of the spring-drive to the moving contact-member assembly substantially in the same manner as already described with reference to Figures 1 to 4.

As regards the detention mechanism, this comprises a three-pointed detention pawl g mounted to oscillate about a fixed stud g a'flanged controlling plate h, 71 fixed to the operating spindle, and a pawl-controlled flyer 2', i i 2' 2' fixed to the sleeve of the moving contact assembly, and except that the controlling element It is made in the form of a circular plate instead of as a quadrant, the mechanism is substantially the same in construction and arrangement as that already described with reference to Figures 1 to 4, and is adapted to operate in substantially the same manner.

Having described our invention, what we claim and desire to secure by Letters Patent is:-

1. A switch of the class described, comprising a support, fixed contacts on the support, a spindle having sleeves thereon and supported by said support, contacts carried by the sleeve, stirrups supported respectively by the spindle and by the sleeves, a quadrant member on the spindle, a control member on the sleeve, a pawl journaled on the support 'for interlocking the quadrant member with the control member, a coil spring supported by the sleeves and having terminals engaging both stirrups, whereby the spring may be placed under tension during the movement of a stirrup.

2. A switch of the class described, comprising a casing having fixed contacts thereon, a spindle journaled in the casing, a sleeve rotatable on the spindle and carrying a contact, two stirrups, one carried by the spindle and the other by a sleeve, a coil spring surrounding the sleeve and having terminals bearing against both stirrups to place the spring under tension during the movement of a stirrup, a star shaped pawl journaled in the easing, a quadrant shaped controlling member on the spindle, a flier on the sleeve adjacent the controlling member and having recesses therein and projections thereon and engaging with the pawl to lock the flier to the controlling member.

3. A switch of the class described, comprising a casing having fixed contacts thereon, a spindle journaled in the casing, a pair of stirrups on the spindle, a coil spring surrounding the spindle and having terminals engaging both stirrups, a quadrant shaped controlling member on the spindle, said member having an arcuate slot therein, a post carried by the casing and operable in said slot, a pawl on the post, a flier having recesses therein and projections thereon engageable with the pawl to control the tension of the spring and a flange on the controlling member engageable with the pawl to hold the same in locked engagement with the flyer.

' H. F. MCLOUGHLIN.

F. W. OSBORN. 

